Spring means

ABSTRACT

A spring means formed integrally with a base the spring means consisting of a number of leaves projecting from the base at spaced intervals around a point, the leaves being all angularly inclined to the base and extending along helical paths in the same direction and being arranged so that spaces are left between them in an axial direction. It is preferred that the base and the leaves are moulded together for example, by injection moulding from a synthetic plastic material. The spring means are of general applicability but have a special application in connection with aerosol valves.

United States Patent [191 Graham et a],

SPRING MEANS [73] Assignee: Samuel Taylor Pty. Limited,

Artarmon, New South Wales,

Australia 221 Filed: Jan. 24, 1972 21 Appl. No.: 220,205

[30] Foreign Application Priority Data [111 3,815,886 June 11, 19743/1959 Campbell 267/180 4/1965 Kahn et al. 267/180 PrimaryExaminer-James Marbert Attorney, Agent, or Firm-Michael S. Striker [57]ABSTRACT A spring means formed integrally with a base the spring meansconsisting of a number of leaves projecting from the base at spacedintervals around a point, the leaves being all angularly inclined to thebase and extending along helical paths in the same direction Jan. 27,1971 Australia 3833/7] and b i arranged so that Spaces are left betweenthem in an axial direction. It is preferred that the base [52] US. Cl.267/180, 267/166 and the leaves are moulded together for example by [5i]Int. Cl Fl6f 1/06 injection moulding from a Synthetic plastic materiaL[58] Field Of Search 267/180, 161, 159, 166 The spring means are ofgeneral applicability but have a special application in connection withaerosol [56] References Cited valves UNITED STATES PATENTS 2.447.3198/1968 De Fourchambault 267/180 7 Claims, 7 Drawing Figures i-waPATENTEDJUH 1 1 I974 SHEET 2 OF 5 FIG.3

1 PATENTEDJUMH 1914 SPRING MEANS This invention relates to spring means,andmore particularly to means for the transfer of resilient pressurebetween two members, as between two relatively displaceable parts of adevice.

Spring means of this type are used in many devices such as check valvesand in any situation in which one part is mounted for limited resilientmovement relative to another part. A particular application, referred tobelow in more detail, is in relation to aerosol valves.

For many uses, especially in aerosol valves, it is of great advantage ifsuch spring means not only posess the necessary resilience but areresistant to corrosion and can be manufactured inexpensively.

It was previously proposed to replace the conventional metal spring inaerosol valves by a single, centrally arranged substantially pin-like orconical element made of a resiliently deformable material, said elementbeing preferably made to be integral with one of the relativelydisplaceable parts of the valve mechanism. Making the resilientlydefonnable element in one piece with one of said parts offered theadditional advantage of simplifying the manufacture of the valvemechanism and, more particularly, its assembly.

While this construction proved to be feasible and advantageous, it wasfound nevertheless that the central element provided only a limitedaxial movement or displacement of the parts relative to each other.

The present invention provides a construction which permits theadvantages achievable by the use of a thrust symmetrically disposed inrelation to the axis of the sealing element of the valve, and also theuse of a noncorrosive material in the construction of the spring meansto be retained, and the further advantage of manufacturing said springmeans integrally with one of the two relatively displaceable members,e.g., with one of the relatively displaceable parts of an aerosol valve.

The present invention consists in spring means which comprise aplurality of elastically deformable leaf elements formed integrally witha base, said leaf elements projecting from said base at spaced intervalsaround a point, the leaf elements being all angularly inclined to thebase and extending along substantially helical paths of the same windingsense and being arranged to leave spaces between them in an axialdirection.

In order that the invention may be better understood and put intopractice a preferred form thereof is hereinafter described by way ofexample, with reference to the accompanying drawings in which:

FIG. I is a median sectional elevation of a check valve incorporatingthe invention,

FIG. 2 is a section on line llIl of FIG. 1,

FIG. 3 is a part sectional plan view on line III-III of FIG. 4 of aspring loaded sliding member in a housing,

FIG. 4 is a sectional elevation on line IVIV of FIG. 3,

FIG. 5 is a sectional elevation of an aerosol valve incorporating theinvention,

FIG. 6 is a sectional elevation to an enlarged scale of the shell ofFIG. 5, and

FIG. 7 is a plan view of the shell.

The check valve shown in FIG. 1 consists of a housing 10 moulded from aplastic material by injection moulding. Moulded integrally with thehousing 10 is the spring means 11 consisting of four individual leaves12 each of which rises from the base of the housing in a helical path,the leaves as seen in plan following arcs of substantially concentriccircles. As shown in FIG. 1 the leaves are spaced apart in an axialdirection.

The housing and the leaves are moulded in a synthetic plastic materialsuch as polypropylene, highdensity, polyethylene, polyamides,polycarbonates, polyurethanes and acetates such as those sold under theTrade Marks DELRIN or CELCON.

The leaves may be arranged as close to each other as may be desired, aslong as there are spaces left between them which make it possible forthem to be independently deformed by a force or pressure appliedthereto, at least a component of which acts perpendicularly to the base.It is not essential to use four leaves but preferably the leaves numberat least three. The crosssectional configuration of the leaves isoptional and may be of any desired shape.

Although separate from each other, the leaves act nevertheless in amanner similar to that of a single coil spring, which means to say thatby pressure exerted on the tips of the leaves, the latter can bedeformed all at the same time, and moved towards the base through adistance substantially corresponding to that of a coil spring in whichthe spacing between consecutive windings corresponds to that between theindividual leaves of the spring means according to the invention, whenthey are not subjected to pressure.

A special advantage of the novel spring means over a coil spring is theuniform application of the pressure caused by the thrust of each of amultitude of resilient parts symmetrically disposed around an axis,instead of the single off-centre thrust of the single-helix coil spring.

Ribs 13 are also moulded integrally with the housing 10 to guide themovement of a ball 14, which constitutes the valve member and seals inan aperture 15 in the cap 16, which screws to the housing 10. The checkvalve operates in a conventional manner to permit the flow of a liquidinto the aperture 15 and out of the aperture 17 in the housing 10 butnot in the reverse direction. From the constructional point of view thefact that the spring means is formed integrally with the housing,provides economic advantages in manufacture and assembly and in use thefact that the spring means may be readily moulded in a corrosionresistant material is advantageous.

In the construction shown in FIGS. 4 and 5 21 is a housing moulded, forexample from plastic material, within the housing is a slide 22 which isfree to slide longitudinally in the housing, being pressed lightlyagainst the right hand wall of the housing by the pressure plate 23,under the influence of the spring means 24, which are moulded integrallywith the pressure plate 23 and which bear on the left hand wall of thehousing. The construction of the spring means 24 is the same as that ofthe spring means 11 of FIGS. 1 and 2.

The embodiment of the invention described above is given to illustratethe generality of its application. The slide 22 could, for example,constitute the slide of a slide projector or any other sliding memberrequired to operate under similar circumstances.

From the embodiment described it will be appreciated that the inventionmay be applied in any situation invention is in connection with aerosolvalves and such an application is illustrated in FIG. 5.

The general construction of the valve shown in FIG. 5 is in the mainwell known, and it is therefore, necessary only to refer briefly to themain component parts to assist in an understanding of the presentinvention. The valve is attached to the opening of an aerosol containerby means of the metal container cap 30, which contains within'it asealing disc, or gasket 31, against the underside of which the peripheryof the cupped flange 32 seals. A discharge tube 33 extends into theinterior of the cupped flange and projects above the periphery of thecontainer cap 30. To the upper end of the discharge tube 33 is attacheda spray tip 34. A generally cylindrical plastic shell 35 fits around thecupped flange 32 within the central part of the container cap 30 beingheld in position by the internal annular rib 35 of the container cap 30.The shell contains within it integrally moulded a spring means 37 whichis arranged centrally in the shell above the passage 38 which leads intothe interior of the aerosol container and into which a dip tube (notshown), which extends to the bottom of the container, is normallyfitted. Surrounding the spring means 37 are a plurality of upstandingintegrally moulded prongs 43.

The shell 35 is shown enlarged in FIGS. 6 and 7. The spring means- 37 isconstructed in substantially the same manner as the spring means 1] ofFIG. 1 and it is therefore unnecessary to describe it further.

The functioning of the valve described is as follows. If the spray tipis displaced by finger pressure to one side of the axis, the cuppedflange is caused to tilt and thus the seal with the sealing disc 31 isbroken and the contents of the aerosol container can pass into .thedischarge tube to be sprayed from the spray tip in a known manner.

The hole 45 in the base of the shell 35 permits gas to be released fromthe upper part of the container together with the liquid or semi-liquidcontents which in some applications is found desirable. The prongs43 areadapted to be engaged by the cupped flange 32 forming a part of thevalve means, and they are deformed by the latter when it is displacedlaterally within the shell by finger pressure applied to spray tip 14 ofthe aerosol valve. The resilient deformation of the prongs acts on theflange and returns it immediately, and automatically, on release of thevalve to its normal or-sealing position, thereby eliminating, or atleast effectively minimising, delay in the closing of the valve on suchrelease.

The spring means according to the invention are also applicable to otherforms of aerosol valves, to eliminate the use of coil springs, or ofother springs required for the valve actuation.

The spring means of the invention may be used where it is desired toestablish end electrical contact, by plating the leaves and apart atleast of the base with a metallic electrically conducting coating. Inthis form the spring means may be used for applying pressure between thebase of an electric torch and a battery contained within it.

In all forms of the invention the leaves may be readily mouldedintegrally with :the base by injection moulding,

using techniques used in moulding screw threads as a" means ofextracting the core of the mould.

We claim:

1. Spring means comprising a base and a plurality of deformable leafelements integral with said base and projecting therefromcircumferentially spaced from each other about acommon axis alongsubstantially helical paths of the same winding sense, each of said leafelements having distant from said base a free end.

2. Spring means as claimed in claim I, and further comprising aperipheral wall integral with said baseand surrounding said leafelements radially spaced therefrom, said peripheral wall being coaxialwith said common axis and projecting :beyond the free ends of said leafelements.

3. Spring means as claimed in claim 1, wherein the base and the leafelements are formed by moulding from a synthetic plastic material.

4. Spring means as claimed in claim 3, wherein said synthetic plasticmaterial is selected from the group comprising polypropylene,high-density polyethylene,

polyamides, polycarbonates, polyurethanes and acetal resins.

'5. Spring means wherein a plurality of spring means as claimed in claim1 are formed on the same base.

6. Spring means as claimed in claim 1, wherein there are four leafelements arranged symmetrically around said axis.

7. Spring means as claimed in claim 1, wherein said leaf elements andpart at least of said base is coated with electrically conductivematerial.

1. Spring means comprising a base and a plurality of deformable leafelements integral with said base and projecting therefromcircumferentially spaced from each other about a common axis alongsubstantially helical paths of the same winding sense, each of said leafelements having distant from said base a free end.
 2. Spring means asclaimed in claim 1, and further comprising a peripheral wall integralwith said base and surrounding said leaf elements radially spacedtherefrom, said peripheral wall being coaxial with said common axis andprojecting beyond the free ends of said leaf elements.
 3. Spring meansas claimed in claim 1, wherein the basE and the leaf elements are formedby moulding from a synthetic plastic material.
 4. Spring means asclaimed in claim 3, wherein said synthetic plastic material is selectedfrom the group comprising polypropylene, high-density polyethylene,polyamides, polycarbonates, polyurethanes and acetal resins.
 5. Springmeans wherein a plurality of spring means as claimed in claim 1 areformed on the same base.
 6. Spring means as claimed in claim 1, whereinthere are four leaf elements arranged symmetrically around said axis. 7.Spring means as claimed in claim 1, wherein said leaf elements and partat least of said base is coated with electrically conductive material.